Stripping down automation sims to the basics, adding in some tower defense and a little rogue-lite action with retro visuals and you have Melt Them All. Combining all the fun elements of each into a tiny package that's good for short bursts, and it's incredibly cheap too. Note: this was a personal purchase.
The idea here is that you can make fuel out of aliens, but you first have to destroy them and then mine away at their little bodies to get the ore. You have to drag around a cart to pick up the ore, and then gradually expand a production chain with lots and lots of conveyor belts.
There's a little survivor-like flavour here too with character buffs to unlock as you go as well, or perhaps a new item to be able to build to spend all your credits. A great distraction when you don't want something too in-depth but with fun game mechanics to keep you wanting to play more.
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The tutorial isn't particularly great but easy enough, and the mechanics are all pretty simple so it doesn't really take long to understand everything you're doing.
Like a lot of smaller games on Steam, it's been a bit buried with only two user reviews. But it's a nice little mix-up on all the survivor-likes coming out lately.
Check it out on Steam. It has Native Linux support.
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